Synthesis of multi-lactose-appended β-cyclodextrin and its cholesterol-lowering effects in Niemann–Pick type C disease-like HepG2 cells

• Keiichi Motoyama,
• Rena Nishiyama,
• Yuki Maeda,
• Taishi Higashi,
• Yoichi Ishitsuka,
• Yuki Kondo,
• Tetsumi Irie,
• Takumi Era and
• Hidetoshi Arima

Beilstein J. Org. Chem. 2017, 13, 10–18, doi:10.3762/bjoc.13.2

• , and bioavailability of drugs. CDs improve the above properties of drugs through complex formation, when formulated as injectable solutions, sprays, eye drops, powders, and tablets [7][8]. In recent years, the efficacy of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) in the treatment of the NPC disease has

Stabilization of nanosized titanium dioxide by cyclodextrin polymers and its photocatalytic effect on the degradation of wastewater pollutants

• Tamás Zoltán Agócs,
• István Puskás,
• Erzsébet Varga,
• Mónika Molnár and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2016, 12, 2873–2882, doi:10.3762/bjoc.12.286

• pollutant of emerging concern (EP), was protected by CMBCD-P against the photocatalytic degradation showing that inclusion complex formation can result in opposite effects depending on the structure of the host–guest complex. Keywords: carboxymethyl β-cyclodextrin polymer; colloid stability; ibuprofen

• bisphenol A was enhanced in aqueous solutions containing β-CD [25], while the photodecomposition of pesticides of similar structure (parathion and paraoxon) was inhibited or catalyzed, respectively, by β-CD [26]. The complex formation can either protect the drug from the effect of light or accelerate the

• in distilled water without any additives (Figure 6 and Table 4) and a slight enhancement in the degradation rate was obtained with nanoTiO2. In the presence of the polymer the rate of degradation decreased suggesting that the complex formation of ibuprofen has a protective effect. Using the CMBCD-P

Biochemical and structural characterisation of the second oxidative crosslinking step during the biosynthesis of the glycopeptide antibiotic A47934

• Veronika Ulrich,
• Clara Brieke and
• Max J. Cryle

Beilstein J. Org. Chem. 2016, 12, 2849–2864, doi:10.3762/bjoc.12.284

• that this is due to the ability of the StaF/X-domain complex to allow substrate reorganisation after initial complex formation has occurred. These results highlight the importance of testing different peptide/protein carrier constructs for in vitro GPA cyclisation assays and show that different Oxy

• Tris pH 7.4 and 150 mM NaCl) at room temperature for 30 min to allow complex formation to occur between StaF and Xsta. Analysis of StaF alone (MW of 47.3 kDa) resulted in overlapping peaks with absorption at λ = 280 and 415 nm at an elution volume of 13.1 mL, whereas when Xsta alone (MW of 53.2 kDa

• this complex allows substrate reorganisation after initial complex formation, which ensures proper substrate orientation in the active site. These results highlight the importance of testing different peptide/protein carrier constructs for in vitro GPA cyclisation assays and show that different Oxy

Interactions between cyclodextrins and cellular components: Towards greener medical applications?

• Loïc Leclercq

Beilstein J. Org. Chem. 2016, 12, 2644–2662, doi:10.3762/bjoc.12.261

• cavity of this molecule is too small to accommodate DNA base pairs. All these results support the work of Hoffmann and Bock who examined the complex formation between different CDs and nucleotides [107]. In contrast, in a more recent work, Jaffer et al. have found that α-CD can form H-bonds with DNA base

Radical polymerization by a supramolecular catalyst: cyclodextrin with a RAFT reagent

• Kohei Koyanagi,
• Yoshinori Takashima,
• Takashi Nakamura,
• Hiroyasu Yamaguchi and
• Akira Harada

Beilstein J. Org. Chem. 2016, 12, 2495–2502, doi:10.3762/bjoc.12.244

• transfer agent (CTA) that has α-cyclodextrin (α-CD) as a host molecule (α-CD-CTA). Prior to the polymerization of N,N-dimethylacrylamide (DMA), we investigated the complex formation of α-CD with DMA. Single X-ray analysis demonstrated that α-CD includes DMA inside its cavity. When DMA was polymerized in

• have been used in the hydrolysis of activated esters [16][17][18][19] and as phase-transfer catalysts [20][21][22][23][24][25][26][27][28]. Moreover, via complex formation, modern supramolecular catalysts [29][30][31][32][33] have been used to achieve various highly efficient and selective reactions

• to studying the polymerization of vinyl monomers, we investigated the complex formation of CDs with vinyl monomers. When mixing α-CD and DMA, we obtained single crystals suitable for X-ray crystallography analysis. The X-ray crystallography analysis is important to understand the complex in the

Efficient mechanochemical synthesis of regioselective persubstituted cyclodextrins

• Laszlo Jicsinszky,
• Marina Caporaso,
• Katia Martina,
• Emanuela Calcio Gaudino and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2016, 12, 2364–2371, doi:10.3762/bjoc.12.230

• poorly soluble in water: the precipitate formed upon acidification by HCl, was filtered and the solid was re-dissolved in the equivalent amount of base. But, it is also true, that complex formation between the MPA and the product, particularly in case of the β-CD version, pointed out that pharmaceutical

Synthesis and properties of fluorescent 4′-azulenyl-functionalized 2,2′:6′,2″-terpyridines

• Adrian E. Ion,
• Liliana Cristian,
• Mariana Voicescu,
• Masroor Bangesh,
• Augustin M. Madalan,
• Daniela Bala,
• Constantin Mihailciuc and
• Simona Nica

Beilstein J. Org. Chem. 2016, 12, 1812–1825, doi:10.3762/bjoc.12.171

• in DPV experiment only the higher value of the anodic peak was observed. For the negative region, there is no counter peak in the 1.0 V to 0.0 V potential ranges. Reactivity towards Hg2+ and Cd2+ complex formation The 2,2′:6′,2″-terpyridine derivatives are known to form stable complexes with

• the possible formation of weak hydrogen bonds in this solvent [44]. For both metal ions similar absorption features were observed. Upon addition of HgCl2 solution, the absorption maxima located at 378 nm and 431 nm are merging into a new band at 421 nm upon mercury complex formation. A progressive

• that a 2:1 complex is formed. The straight slope and its saturation at a ratio of 0.5 indicate a high binding constant which cannot be determined from this set of data. To assess the terpyridine-metal complex formation, 1H NMR titration of 4a with HgCl2 has been performed. The addition of 0.25

Amidofluorene-appended lower rim 1,3-diconjugate of calix[4]arene: synthesis, characterization and highly selective sensor for Cu²⁺

• Rahman Hosseinzadeh,
• Mohammad Nemati,
• Reza Zadmard and
• Maryam Mohadjerani

Beilstein J. Org. Chem. 2016, 12, 1749–1757, doi:10.3762/bjoc.12.163

• peak of aromatic ring hydrogen atoms (Hc, resonated at 7.35 ppm) was converted to two distinct peaks at 7.20 and 6.95 ppm (Hc1, Hc2). In addition, signals belonging to the fluorene moieties and tert-butyl groups, which are quite far away from binding site, were also affected by complex formation. For

• during the complex formation. The fact that receptor L shows a sensitive recognition affinity to copper ions and a much more obvious shift of 1H NMR peaks in the presence of Cu2+ is actually not surprising because of a relatively rigid binding pocket of receptor L providing four sites of NH and OH which

• allows a suitable complex formation with a copper ion (Scheme 3). To show the high selectivity of chemosensor L for copper ions, the association constant and limit of detection (LOD) were compared with those reported for other related chemosensors (Table 1). It should be emphasized that due to different

From steroids to aqueous supramolecular chemistry: an autobiographical career review

• Bruce C. Gibb

Beilstein J. Org. Chem. 2016, 12, 684–701, doi:10.3762/bjoc.12.69

• , the extra methylene group of butane meant that it bound to the host twelve times more strongly than propane, and this allowed selective butane complex formation from a 1:1 propane–butane mixture (Figure 12). In short, aqueous solutions can be used to separate gases; to paraphrase Cram, the synthesis

Interactions between 4-thiothymidine and water-soluble cyclodextrins: Evidence for supramolecular structures in aqueous solutions

• Vito Rizzi,
• Sergio Matera,
• Paola Semeraro,
• Paola Fini and
• Pinalysa Cosma

Beilstein J. Org. Chem. 2016, 12, 549–563, doi:10.3762/bjoc.12.54

• affecting the electron-transfer processes by changing the diffusion coefficient of the electroactive molecule by inclusion complex formation. Experiments, in the presence of glucose, mimicking the external interaction between CDs and S4TdR, were also performed with the same molar ratios of 1:1, 1:5 and 1:10

• chemical shifts of the guest protons are often reported as an indication of the inclusion complex formation [10]. As reported in Figure S1A (Supporting Information File 1), in which the observed Δδ values (see Equation 3) are shown, the most part of S4TdR protons exhibited an oscillating behavior, when the

Aluminacyclopentanes in the synthesis of 3-substituted phospholanes and α,ω-bisphospholanes

• Vladimir A. D’yakonov,
• Alevtina L. Makhamatkhanova,
• Rina A. Agliullina,
• Leisan K. Dilmukhametova,
• Tat’yana V. Tyumkina and
• Usein M. Dzhemilev

Beilstein J. Org. Chem. 2016, 12, 406–412, doi:10.3762/bjoc.12.43

• molybdenum complexes. For example, 3-hexyl-1-phenylphospholane and 3-benzyl-1-methylphospholane react with Mo(CO)6 furnishing molybdenum complexes 13b and 14g (Scheme 7). The complex formation is evidenced by changes in the NMR spectral parameters of compounds 13b and 14g in relation to the initial

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• by reacting β-CD with tosyl imidazole (TsIm) [15]. Great advantages, in terms of yields, reaction times and product purity, were obtained by using a cavitating tube (40 min, 19.2 kHz, 20 W, yield: 55%). Thanks to the fast US-assisted inclusion complex formation between β-CD and TsIm reaction times

Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

• Sophie Letort,
• Sébastien Balieu,
• William Erb,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2016, 12, 204–228, doi:10.3762/bjoc.12.23

• technics [43]. Despite the pronounced solubility changes consistent with complex formation, little variations in the UV spectra, combined with the guest’s small chemical shifts observed in 1H NMR experiments (0.01–0.06 ppm), suggest the formation of external complexes rather than an inclusion complex

• . However the inclusion complex formation was strengthen by molecular modeling studies with the aromatic group included into the cavity. Finally, DSC curves showed a first endothermic portion starting at 225 °C, typical of a melting process, and a second sharp exothermic decomposition peak, proving the

• binding constant values and the hydrophobicity of the pesticides, suggesting that steric effects are probably predominantly involved in complex formation. The inclusion of the apolar heterocyclic ring into the CD cavity is the most likely situation to occur. γ-CD has the largest secondary alcohols rim

Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques

• Gabor Benkovics,
• Ondrej Hodek,
• Martina Havlikova,
• Zuzana Bosakova,
• Pavel Coufal,
• Milo Malanga,
• Eva Fenyvesi,
• Andras Darcsi,
• Szabolcs Beni and
• Jindrich Jindrich

Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11

• that the position of the cinnamyl group plays an important role in the intermolecular complex formation. Keywords: capillary electrophoresis; cyclodextrin derivatives; mono-cinnamyl; regioisomers; supramolecular structures; Introduction Supramolecular polymers (SP) are aggregates of monomer units

• requirement for the effective SP formation. In the case of 6-O-monobenzoyl-β-CD, for example, the direct attachment of the phenyl moiety to the CD rim did not result in intermolecular complex formation [6]. On the other hand too long and flexible spacers between the host and the guest moiety favored the self

• that the cavity of the CD shows distinguishable inclusion affinities towards different substrates, even to homologues and isomers. A self-sorting complex formation ability was described for the two regioisomers of monocinnamoyl-α-CD (Cio-α-CD) [9]. While the 2-Cio-α-CD isomer formed an insoluble double

Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol

• Miriana Kfoury,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5

• Phase solubility studies are widely used to evaluate the ability of CDs to increase the aqueous solubility of the guests. They also lead to the determination of diverse parameters involved in complex formation such as Kf value, complexation efficiency (CE), optimal molar ratio for solid inclusion

• lipophilic cavity. This supported the fact that hydrophobic forces play a leading role in inclusion complex formation. Although ΔE values clearly illustrate the stability of each inclusion complex, it has to be underlined that such theoretical energies cannot be directly compared to Kf values, as the

Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

• Waratchada Sangpheak,
• Jintawee Kicuntod,
• Roswitha Schuster,
• Thanyada Rungrotmongkol,
• Peter Wolschann,
• Nawee Kungwan,
• Helmut Viernstein,
• Monika Mueller and
• Piamsook Pongsawasdi

Beilstein J. Org. Chem. 2015, 11, 2763–2773, doi:10.3762/bjoc.11.297

• β-CD at different temperatures in the range of 15–45 °C [42]. The temperature parameter contributes to the strength of the interaction between the host and guest molecules in complex formation. Size matching of the host and guest molecules also dominates complex stability. Our results showed that

• flavanones and their complexes. (A) hesperetin and (B) naringenin. Complex formation was by freeze-drying. The influence of flavanones and their complexes on IL-6 secretion from LPS-stimulated macrophages. Cytotoxicity of free flavanones and their inclusion complexes on different cancer cell lines. The

Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction

• Mino R. Caira,
• Susan A. Bourne,
• Halima Samsodien and
• Vincent J. Smith

Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281

• complex formation between 2ME and both of the host molecules was finally confirmed by comparing the FTIR spectrum of pure 2ME with those of the pure CD and the putative CD-2ME inclusion complexes prepared by kneading; characteristic bands for 2ME (at 1600, 2861, 2903, 3179 and 3413 cm−1) were seen to

• consistent with inclusion complex formation. A PXRD trace of the material did not match any of those generated for known polymorphs of the pure host DIMEB [16], again supporting the formation of an inclusion complex between DIMEB and 2ME. As for the characterization of the β-CD·2ME complex described above

• illustrate for the first time details of the encapsulation of a ‘classical’ steroidal molecule by cyclodextrin hosts. In addition, from the variety of host and guest conformations observed in the TRIMEB·2ME complex, even in one crystal, it is evident that complex formation involves some degree of ‘mutually

Co-solvation effect on the binding mode of the α-mangostin/β-cyclodextrin inclusion complex

• Chompoonut Rungnim,
• Sarunya Phunpee,
• Manaschai Kunaseth,
• Supawadee Namuangruk,
• Kanin Rungsardthong,
• Thanyada Rungrotmongkol and
• Uracha Ruktanonchai

Beilstein J. Org. Chem. 2015, 11, 2306–2317, doi:10.3762/bjoc.11.251

• in such studies may result in ternary (host:guest:co-solvent) complex formation. The objective of this work was to investigate the effect of ethanol as a co-solvent on the inclusion complex formation between α-mangostin (α-MGS) and β-CD, using both experimental and theoretical studies. Experimental

• phase-solubility studies were carried out in order to assess complex formation, with the mechanism of association being probed using a mathematical model. It was found that α-MGS was poorly soluble at low ethanol concentrations (0–10% v/v), but higher concentrations (10–40% v/v) resulted in better α-MGS

• -solvent on the complex formation between α-mangostin (α-MGS) and β-CD. Phase solubility studies were carried out in order to assess the formation of those complexes at various β-CD concentrations, with ethanol as a co-solvent. A simple mathematical model was then applied to explain the solubility of α-MGS

Cholesterol lowering effects of mono-lactose-appended β-cyclodextrin in Niemann–Pick type C disease-like HepG2 cells

• Keiichi Motoyama,
• Yumi Hirai,
• Rena Nishiyama,
• Yuki Maeda,
• Taishi Higashi,
• Yoichi Ishitsuka,
• Yuki Kondo,
• Tetsumi Irie,
• Takumi Era and
• Hidetoshi Arima

Beilstein J. Org. Chem. 2015, 11, 2079–2086, doi:10.3762/bjoc.11.224

• , etc., through complex formation [5][6]. Recently, 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) has attracted considerable attention for the treatment of NPC disease [4][7][8][9]. The administration of HP-β-CyD to NPC1-knock out (Npc1−/−) mice has been reported to remarkably prolong the life span of the

• adamantane, which is often used as a guest molecule for β-CyD, using the quartz crystal microbalance method (QCM) in phosphate-buffered saline (PBS, pH 7.4) at 37 °C. As a result, the dissociation constant of Lac-β-CyD with adamantane was 9.8 × 10−7 M due to the potent complex formation. Therefore, this

Consequences of the electronic tuning of latent ruthenium-based olefin metathesis catalysts on their reactivity

• Karolina Żukowska,
• Eva Pump,
• Aleksandra E. Pazio,
• Krzysztof Woźniak,
• Luigi Cavallo and
• Christian Slugovc

Beilstein J. Org. Chem. 2015, 11, 1458–1468, doi:10.3762/bjoc.11.158

• conducted by BP86//SVP, solvent effects were added by single point calculations using M06//TZVP functional (cf. Supporting Information File 1). The first question tackled concerned the anticipated coordination of the carbonyl group in compound 15 to form the corresponding 18-electron complex. Formation of

Single-molecule conductance of a chemically modified, π-extended tetrathiafulvalene and its charge-transfer complex with F₄TCNQ

• Raúl García,
• M. Ángeles Herranz,
• Edmund Leary,
• M. Teresa González,
• Gabino Rubio Bollinger,
• Marius Bürkle,
• Linda A. Zotti,
• Yoshihiro Asai,
• Fabian Pauly,
• Juan Carlos Cuevas,
• Nicolás Agraït and
• Nazario Martín

Beilstein J. Org. Chem. 2015, 11, 1068–1078, doi:10.3762/bjoc.11.120

• , suggesting no complexation. The solvent was then changed to acetonitrile, a more polar solvent better able to stabilize complex formation, but this too did not give the anticipated strong color change. Only when the solution was heated at reflux for 3 h under ambient conditions and a large excess of TCNQ was

Terminal lipophilization of a unique DNA dodecamer by various nucleolipid headgroups: Their incorporation into artificial lipid bilayers and hydrodynamic properties

• Emma Werz and
• Helmut Rosemeyer

Beilstein J. Org. Chem. 2015, 11, 913–929, doi:10.3762/bjoc.11.103

• , equimolar amounts of complementary and non-complementary DNA strands as well as a SYBR Green I solution were added to the bilayer-bound lipo-oligonucleotide. The kinetics of the ternary complex formation at the bilayer surface as well as the stability of the complexes against perfusion was measured by

Multivalent dendritic polyglycerolamine with arginine and histidine end groups for efficient siRNA transfection

• Fatemeh Sheikhi Mehrabadi,
• Hanxiang Zeng,
• Mark Johnson,
• Cathleen Schlesener,
• Zhibin Guan and
• Rainer Haag

Beilstein J. Org. Chem. 2015, 11, 763–772, doi:10.3762/bjoc.11.86

• at N/P ratios between 2 to 4. The binding capacity of all vectors was slightly different from each other. The results of this assay clearly display that all synthesized vectors were able to form polyplexes with siRNA at low N/P ratios. Moreover, the complex formation ability of the new vectors is

Discrete multiporphyrin pseudorotaxane assemblies from di- and tetravalent porphyrin building blocks

• Mirko Lohse,
• Larissa K. S. von Krbek,
• Sebastian Radunz,
• Suresh Moorthy,
• Christoph A. Schalley and
• Stefan Hecht

Beilstein J. Org. Chem. 2015, 11, 748–762, doi:10.3762/bjoc.11.85

• only contributes to binding enhancement, but also helps to exert control over complex formation. For example, “molecular elevators” have been constructed by Stoddart et al. [30][31] and giant porphyrin wheels were prepared by Anderson and co-workers [32][33], both using a multivalent template strategy

Probing multivalency in ligand–receptor-mediated adhesion of soft, biomimetic interfaces

• Stephan Schmidt,
• Hanqing Wang,
• Daniel Pussak,
• Simone Mosca and
• Laura Hartmann

Beilstein J. Org. Chem. 2015, 11, 720–729, doi:10.3762/bjoc.11.82

• protein receptors are formed to control cell–cell recognition, cell adhesion and related processes. The aim of this work is to shed light on the principles of complex formation between surface anchored carbohydrates and receptor surfaces by measuring the specific adhesion between surface bound mannose on

• generally low affinity between sugars and receptors and possibly also by the high flexibility of the polymeric mannose linkers [9]. High molecular flexibility causes a high degree of conformational entropy that negatively affects complex formation between ligands and receptors [23]. Also the design of the